I think Apple does pretty good with its macOS software updates throughout the year. I really like the MRT security updates built into the macOS. Until now, I have had my Mac automatically install security updates. Unfortunately, a recent MRT update installed by Apple caused people major grief. It was withdrawn by Apple and subsequently replaced with a fixed version. This has made me rethink installing security updates automatically, so I turned that setting off. If you would like to turn off that setting, here is how you do it.
Before I get into this setting I urge you to go to this site and read this article. It is written by a person that has a software App called SilentKnight which shows what security updates, if any, your Mac needs. The newest version of this software allows you to install specific updates incrementally which is great.
By the way, the App is free, I urge you to download and use it. But I digress.
To change your security update setting just go into the “Software Update” Pref Pane.
When in this window, click on the “Advanced” button.
Previously, I have had this checked. I will leave this unchecked going forward.
So, if you leave that unchecked, how do you install security updates? I think the best way is to use the SilentKnight App. Apple pushes security updates in the background. The idea is they are to be installed automatically. I monitor websites that mention it when security updates are pushed out. If you do not follow these type of websites, then you should just run the SilentKnight App once a week. If it lists a security update, you can choose to install it or wait a bit while doing a little research.
This may be a little more detailed than you like, but a if security update messes up your Mac you will be down for the count until you reinstall the OS.